Apparatus for making phonograph records



R. HEAD. APPARATUS FOR MAKINGPHONOGRAPH RECORDS.

LICATION l APR-11.19l9- I I Patented J 11613, 1922.

ROBERT HEAD, OF YONKERS, NEW YORK, ASSIGNOR TO THE AEOLIAN COMPANY, A CORPORATION OF CONNECTICUT.

APPARATUS FOR MAKING PI-IONOGRAPH RECORDSQ Original application Serial No. 14,404, filed March 15, 1915. Divided and this applicationfiled April 11, 1919. Serial No. 289,372.

To all whom it may co cern Be it known that I, Bonner Hi An, a citizen of the United States of America, residing at Yonkers, in the county of Westches:

' adapted to be used in the making of the commercial records may be made in such a manner that the sound waves of the original record will be accuratelyreproduced in the copy but imperfections in the original will be practicallyeliminated from the copy, the copy possesslng other advantages over those made in the usual manner, as will hereinafter appear.

To these and other ends the invention consists in certain improvements and combinations and arrangements of parts, all as will be hereinafter more fullydescribed, the features of novelty being pointed out partioularly in the claims at the end of the specification. Y

In the drawing, whichillustrates the preferred embodiment of theinvention Figure 1. is a top plan viewof an apparatus constructed inaccordance with the present invention;

Figure 2 is a view,'partly in section and partly in elevation, of the apparatus as shown in Figure 1; v

Figure 3 is a diagrammatic view on an enlarged scale. illustrating the manner in which the tracer cooperates with the original record from which the copy is to be made;

Figure 4 is a fragmentary View showing the appearance'of the sound grooves in the original; and j Figure 5 is a fragmentary view showing grooves produced in the copy.

Similar parts are represented by the same reference characters in the several views.

The present invention provides an apparatus which is capable ofuse generally where it is desirable or necessary to produce pan tograph1c coples from originalswhich are Specification of Letters Patent. P t t June 13, 1922,

rough; or otherwise contain imperfections Y which should be practically eliminated from the copies. The apparatus is especially adapted for use in the production of phonograph records of the disk type having lateral or zlg-zag sound waves, by a method such as that described in my application Serial No. 14,404, filed March 15, 1915, ofwhich application the present is a division.

The preferred embodiment of the inven tion is shown in the accompanying drawing and will be hereinafter described in detail.

It is to be understood, however, that the invention is not restricted to the precise constructlon as equivalent constructions are contemplated and will be included within the scope of the claims. v

In the presentinstance, the apparatus comprises a suitable base 1 which supports a pair of turn tables 2 and 3. These turn tables are mounted on parallel axes or spindles 4 and 5 and they are revolved in synchronism or at the same speed by any sultable mechanism which operates a shaft 6 which i connected to the turn tables by, the spiral'gearing 7 and 8. 9 from which the copy is to be made is fixed on the turn table3 whilethe blank or plain disk 10 which subsequently becomes the copy is fixed on the turn table 2. In the present instance, the copy will be one-half the slze of the original, this reduction presenting the advantage that imperfections in the original will be reduced correspondingly with the reduction in the size of the copy.

An arm 11 which is of rigid construction is supported by the bearing 12 to swing in a plane parallel to the plane of the original and the copy. This arm extends through a slot 18 formed in'a stationary guide member 14, the upper wall 15 of the slotbeing parallel to the plane of the original and the copy. The guide member is preferably:

curved or concentric with the axis ofthe bearing 12, as shown. A spring 16 on the under side of the bar 11 bears on the lower The original wall 17 of the slot and this spring acts to yieldingly press and hold the top of the arm 11 against the top wall 15 of the slot, thus insuring movement'of the arm 11 in a true plane. A tracer 18 is carried by the arm 11 toward it free end. The point or operative end of the tracer is rounded as shown in Figure 3 and the tracer is yieldingly supported in the arm 11 so that it may move in a direction transverse to the plane in which the arm swings. As shown, the tracer is slidable freely in a bore 19 in the arm, the tracer having a reduced portion of'stem 20 which is slidable in a cap 21 threaded in the bore 19, and a compression spring 22 is coiled about the stem 20 and bears at its ends on the tracer and the cap respectively. As a result, the rounded point of the tracer is always pressed yieldinglyinto operative relation with the sound groove 28 or other line to be followed on the origina'h Where the original fromwhich the copy is to be made comprises an etched record produced in accordance with the method described in my application 'hereinbefore referred to, the rounded point or end of the tracer will be maintained yieldingly in contact with the edges of the sound grooves notwithstanding irregularities andtvariations in the width or. shape of the groove resulting from the etching operation. This yielding pressure upon the tracer will not only vmaintain the tracer in cooperative relation with the grooves so that it will follow the groove, but it will also center the tracer between the two walls or edges of the groove even though the groove may vary in width or shape or have other irregularties, in consequence of which the axis of the tracer will follow the median line of the groove and it will reproduce in the copy a groove which conforms with the median lineof the groove in the original and, hence, the ir-regulari ties of the original will be substantially corrected or eliminated in the copy. The copy is made on the blank 10 by a tracer cutting or other type of record forming tool 24. A

cutting tool is shown in the present instance it being preferably so shaped that it will produce a distinctively V-shaped groove 25 in the copy. A groove of this form willkeep the reproducing stylus well down in the groove with the advantage that the reproduction of sound is more accurate and it is of greater volume. In view of the fact that the tool 2% is mechanically guided instead of acoustically driven as in the usual recording method in which the cutting tool is attached to the recording diaphragm, a much deeper sound groove canbe produced than has heretofore been found practicable. Furthermore, the mechanical guiding of the copying tool enables records to be made not only in wax-like materials but such records can be made in any appro priate metal such, for example, as steel, and the like. If the record is made in steel, it may be subsequently hardened and used as a dye. A thin sheet of soft steelor nickel or other appropriate metal may be 1. In combination, means for rotatably supporting a zig-zag grooved sound record anda record blank, a tracer having a rounded end wider than the groove of the sound record, a record-forming tool, and means operativel connecting the tracer and tool, said tool fbrming a record on said blank as the tracer follows said groove, the tracer being movable relatively to the tool whereby the tracer is yieldingly pressed into the,

groove so as to contact with" both sides thereof and to compensate for variations in the distance between the portions of the sound record engaged by the tracer and the plane in which the tool operates.

2. In combination, a pivoted pantograph arm, a tracer located toward the free end of said arm, means for rotatably supporting a zig-zag sound record to be followed by said tracer, a record-forming tool on said arm between its pivot and said tracer, and means for rotatably supporting a recordblank to be operated on by the record-forming tool. Y

3. In combination, a pivoted pantograph arm, a tracer located toward the free end of said arm, means for rotatably supporting an enlarged zig-Zag sound record to be followed by said tracer, a record forming tool on said arm between its pivot and said tracer, and means for rotatably supporting arecord blank to be operated on by the record-forming tool, the axis of said rotatable supporting means and'the pivot of the pantograph arm being in alinement.

4. The combination of a support for a zig-zag grooved sound record, a support for a record-blank, means for moving said supports concurrently, mounted to swing across the record and rec- 'ord-blank, a tool connected to 'said arm and operative on the record-blank, and a tracer connected to said arm and having a roundedportion which is wider than and is adapted to cooperate with the groove in the record.

substantial a pantograph arm 7 5. The combination of rotatable supports 1 for a zig-zag sound record and record-blank respectively, means for revolving said supv ports synchronously, a pantograph arm mounted to swing in a plane parallel to the record and record blank, a tool connected to said arm and operative on the'record blank, and a tracer connected to said arm havlng a rounded end wlder 'than and cooperative with the edges of the groove in the pivoted to swing across said supports and record, said tracer being yieldable relatively connected to a tracer which cooperates with to said arm in a direction transversely of the the sound record and a tool which cooperates plane in which said arm swings to compenwith said blank, a guide, and means for 5 sate for variations in the width of th holding said arm in engagement with said 15 groove in the sound record. guide whereby the arm is caused to swing 6. The combination of rotatable supports in a true plane. for a zig-zag sound record and a record- In testimony whereof I have hereunto set blank respectively, means for revolving said my hand. 10 supports synchronously, a pantograph arm ROBERT HEAD. 

